A bicyclist pumps his or her pedals, one with the right foot and one with the left foot. A pianist may press down on one of perhaps three pedals, one of which may be a damper pedal. The driver of a car presses down on a brake pedal to stop and an accelerator pedal to go.
Such pedals are different. The common bicycle pedal has two sides, each of which swings up and down about a common pivot point, and the common pivot point in turn rotates planet like around a second pivot point. A piano pedal has two ends, one of which is pushed down by a foot, an action that pivots the other end of the pedal up to push a rod up to raise, for example, dampers off piano strings to keep the strings vibrating. The common brake pedal has no pivot locations immediately at the pedal itself; the pedal or relatively wide piece that confronts the foot is fixed rigidly to a shaft or rod that pivots at a distance from the pedal. The common accelerator pedal may have a pivot point at least at one end of the pedal.
A pedal may be a lever. A lever may be defined as a machine that includes a beam or rigid rod that is pivotable at a fixed hinge or fulcrum. A lever may be defined as a beam connected to a structure or its environment by a hinge, pivot or fulcrum.
A pedal is typically an active or moving part of a mechanism. That is, activation or a pressing upon the pedal transmits a force to another part of the mechanism.